The function of endothelium, nerve and blood cells in microcirculation.-The effect of hypoxia and acidosis-

本研究探讨了神经、内皮细胞和血细胞对微血管张力的影响。为了使该方案可行，使用该仪器安装微血管存在一些问题。使用该仪器的文献很多。然而，我们发现浴槽内的温度不均匀，这对实验不利。首先，我们将浴槽容量改为1ml，浴槽温度保持在0.5℃以内。其次，我们没有在血管腔内灌注液体，因为我们不能得到恒定的流动。第三，在血细胞对微血管张力影响的实验中，我们改变了实验方案：1。我们将白细胞（WBC）直接放入浴缸中。2.我们使用了专门设计的浴槽，通过镍铬合金丝加热，浴槽温度保持在37℃。3.我们使用Hepes缓冲液代替Krebs溶液，因为Krebs溶液的曝气干扰了微米直径的测量。5%的二氧化碳曝气是保持克雷布斯溶液pH值7.4的必要条件。我们使用上述仪器，在猪的脊柱和冠状血管上得到了以下结果。1.缓激素是检测内皮存在与否的有效药物。2.跨壁电刺激（20mA，持续时间0.3msec, 1Hz）引起轻微收缩。然而，这种收缩不是由去甲肾上腺素引起的，因为直接应用去甲肾上腺素会引起扩张。有必要进一步研究哪种递质参与了这种收缩。3.在冠状血管中，缺氧增强了白细胞诱导的血管舒张。脊髓前动脉，白细胞10^4 ~ 10^6个细胞/ml，诱导血管舒张。由于这种不透明的溶液，我们无法在10^7 WBC存在的情况下测量微血管的直径。4.二氧化碳本身收缩脊髓动脉，而低pH值（酸中毒）扩张。从这些发现可以看出，微血管对各种环境变化的反应与大血管不同。少

This study examined the role of nerves, endothelium and blood cells on the tone of microvessels. TO persuade this protocol there are some problems using the instrument to mounting the microvessels. There are many literatures to use this instrument. However, we found that there is an inhomogeneity of temperature within the bath that is not good for the experiment. Firstly, we changed the bath capacity to 1 ml and kept the bath temperature within 0.5C.Secondly, we did not perfuse the fluid within the lumen of the vessels, because we could not get the constant flow. Thirdly, in experiment for the effect of blood cells on the tone of microvessels we changed the experimental protocol : 1.We administered white blood cell (WBC) directly to the bath. 2.We used specially designed bath, in which temperature was kept constant 37C by heating with Nichrome wire. 3.We used the Hepes buffer solution instead of Krebs solution, since aeration of Krebs solution disturbed the measurement of diameter of m … More icrovesses. Aeration with 5% carbon dioxide is necessary to keep the pH of Krebs solution 7.4. We used the above mentioned instruments and got the following results using porcine spinal and coronary vessels. 1.bradykinin is a useful drug to test the presence or absence of endothelium. 2.Transmural electrical stimulation (20mA,duration 0.3msec, 1Hz) induced a slight contraction. However, this contraction was not caused by norepinephrine, since directly applied norepinephrine induced dilation . Further study is necessary what transmitter may be invol ved in this contraction. 3.In coronary vessels, hypoxia potentiated the WBC-induced vasodilation. In antherior spinal artery, WBC,10^4 to 10^6 cells/ml, induced vasodilation . We could notmeasure the diameter of the microvessels in the presence of 10^7 WBC because of this opaque solution. 4.Carbon dioxide itself contracted spinal artery, whereas low pH (acidosis) dilated. From these findings it seems that the response of microvessels to various environmental changes was different from that of large vessels. Less